Change in the pratices and representations of small-scale fish farming activity: a partnership research process in west cameroon




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8th International Symposium on Tilapia in Aquaculture 2008

8th International Symposium on Tilapia in Aquaculture 2008


CHANGE IN THE PRATICES AND REPRESENTATIONS OF SMALL-SCALE FISH FARMING ACTIVITY:A PARTNERSHIP RESEARCH PROCESS IN WEST CAMEROON

BOGNE SADEU C.1*, O. MIKOLASEK 2, B. BARLET 3, E. CHIA 3,

V. POUOMOGNE4 and M. TOMEDI EYANGO5

1 : Département de Foresterie, FASA ; Université de Dschang, BP 383 Dschang

2 : UPR Aquaculture, CIRAD ; TA B-20/91 BP 5095 – 34196 Montpellier Cedex 05 - France

3 : UMR Innovation, CIRAD, TA C-85/15 34398 Montpellier Cedex 5 - France

4 : IRAD BP 139 Foumban

5 : Département de Foresterie, FASA, Université de Dschang, BP 383 Dschang

* : Auteur correspondant : cbognesadeu@yahoo.fr

Abstract

¶The present study aims at analyzing the fish farming practices of West Cameroon fish farmers, and the representation which they had of their activity within the framework of a project of research-action-in-partnership. ¶The practices were characterized before and after the partnership was implemented, starting with the data which resulted from talks and observations, then evaluate performances of the new practices built by the farmers and the researchers. Finally, the main factors inducing the change of the representation that the farmers have of their activity, are highlighted. The results obtained showed the farmers’ will of change. The new practices had a positive impact on the production. The better average individual fish weights and the yields at harvest induced the farmers to re-think the fundamental aspects of their activity mainly: quality of the pond infrastructures, management of pond water, utility of an in pond compost crib, stocking densities and role of catfish in the pond to support both the production and the predation on the tilapia fry. The evolution of the farmer’s representations from seeing the fish as an object of leisure to seeing it as an animal which should find enough to eat and grow could lead towards a commercial and profitable fish-farming.

Key words: practices, representations, fish farming, research action in partnership,

INTRODUCTION

In humid tropical Africa, it is known that a number of countries try to integrate fish farming into their production systems. These attempts bespeak an innovative dynamics perhaps induced by external factors such as projects and research programs. Despite important advances afforded by agronomic systems since the 1970s in research-development, taking account of farmers’ needs in order to define research projects has not been done in association with farmers but through external diagnoses. Researchers and extension agents imagine new ways of producing even while they know little or nothing about practices and projects deployed by the potentially concerned farmers (Girard 2006). This translates, on the field, into mitigated performances of proposed production systems. In Cameroon, 60 years after introduction of fish farming, annual production stands at 337 tons according to FAO (2005). The objective of the present study is to examine the practices and representations of aquaculture activities by the farmers and to monitor the process of evolution of these practices and representations. This falls within the wider objective to develop on a sustainable base commercial fish farming «models» integrated into family agricultural farms.

I-DEFINITION OF A RESEARCH PROBLEM: CONTEXT, QUESTIONS AND METHOD

Fokoué Sub division is found in the Menoua Division in the West Province of Cameroon. It is located between latitudes 5° 20’ and 5° 22’ North and longitudes 5° 10’ and 5° 15’ East. The average altitude is 1 400 meters. The temperature is moderated by the altitude and stands at an average of 20.26° C. The average rainfall is 1853.8 mm.

Research-Action in partnership is a process which involves field actors equipped with a willingness to change, and researchers with a research intention (Liu 1997). The formulation of the common problem to be solved has been expressed during the first phase of diagnosis which lasted from 2004 to 2006. It consisted at first of realizing a diagnosis of inserting fish farming into the family farms of Menoua and of organizing collective restitution of results, followed by their discussion with farmers. This diagnosis has enabled to identify the active fish farmers and to pinpoint Fokoué as one of the study zones. A meeting of these stakeholders has led to the implementation of two groups, one of farmers and the other one of scientists. Thereafter, the links between the two groups have been strengthen formalized through a partnership agreement which spells out the rights and duties of each of the two groups (Chia et al 2008). Finally, a dozen of the 23 identified fish farmers (members of the farmer’s group) volunteered to experiment the new practices short listed. The method used to reach the objective of the present study is based on the following points (Landais 1996):

  • Direct observation of practices in order to know how and what farmers effectively do (study of the modality of practices);

  • Measuring production performances in order to build the indicators which are necessary to compare and evaluate the results obtained by the different actors (a study of the efficiency of the practices);

  • Dialogue with the actors is always associated with the two methods described above. It is the main means of research on farmer practices as well as on reasons inducing their choices;

  • These methods allow us not only to favor individual and collective learning, they also offer opportunities for interpreting the set of past results and to constitute a common reference.

II- PRATICES AND REPRESENTATIONS OF FISH FARMING ACTIVITIES IN FOKOUE BEFORE EXISTENCE OF PARTNERSHIP

II-1. Fish farmer's practices

Practices refer to the set of material and regular activities, intentional or not, which farmers develop within the framework of conducting the process of their agricultural production: the way of doing. They can be more simply defined as « the farmers’ concrete action manners » (Landais and Deffontaines 1988).

More than 90% of ponds are constructed by derivation in the lowlands. They are small in size (100m² in average). The average depth is about 0, 7 meters and feeder canals are made of earth. The outlet device is made of an assemblage of PVC pipes and elbows. Compost crib which covers less than 5% of the pond surface can also be found in a corner of the pond. In the past, some fish farmers constructed piggeries over their ponds but this practice has been abandoned because the pigs were often stolen.

II-1-1. Stocking practices

The monoculture of the Nile tilapia, Oreochromis niloticus, is the dominant practice. Fingerlings of the Nile tilapia are harvested from the prior drainage of the pond during which juveniles of less than 10g are kept alive, stored and re-stocked for a following production cycle. The stocking density is above 3 fingerlings /m² for more than 70% of fish farmers.

Some farmers associate the African catfish, Clarias sp., as a secondary species to the stocked tilapia. This association depends on the availability of juveniles of the latter species, which is either supplied by IRAD fish farming experimental station in Foumban or by private hatcheries or, caught from the wild. Purchase is collectively done. High prices and transport mortalities are cited as the major constraints to use catfish fingerlings.

II-1-2. Fertilization practices and feeding of the fish

The use of fertilisers in compost crib does not follow a regular pattern. It is during the cleaning of farms and pond surroundings that compost cribs are loaded. Banana (Musa sp.) and some other plant leaves can cause mass fish mortality and are consequently proscribed for pond fertilization.


II-1-3. Draining practices and destination of products

Pond drainage usually takes place two to three years after stocking. It mostly occurs during the Christmas and New Year festivals. Some days prior to the drainage, fish farmers inform neighbors in order to sell their harvest beside the ponds. The existence of drainage devices in more than 90% of ponds makes the evacuation of the water easy. Picking up of fish from the bottom of drained ponds is done by using baskets and buckets. For ponds without drainage devices, a gutter is created across the down-stream dam. The absence of 75% of initially stocked catfishes is explained by mystic practices and predation by certain predators. The final individual weight of tilapias is generally less than 100g, and that of the rare harvested catfish sometimes exceeds 2500g.

After pond drainage, farmers dredge and dry the bottom mud which is eventually used to fertilize crop farms.

Harvests are generally so low that they are totally consumed by the family. Only 32% of fish farmers sell a part of their harvests.

II-2 Representations

The elaboration of these practices is closely linked to the farmer’s perception of the fish and to the role of fish in the social relations and as source of income.

As a product, fish does not need to be particularly fed. The more there are fish in the water, the more fish shall be harvested; pond depth has no importance; pond water has to be renewed with regularity; the disappearance of fish from the ponds is related to predation and to mystic practices.

In the social relations, no role is given to the farmed fish. Close to 30% of the fish farmers have never harvested their ponds and only 30% of them have ever been satisfied with their harvests. Selling, if any, takes place beside the pond, just after harvesting and fish are rarely transported to the market square. A little proportion of the harvest is the object of gifts to close ones and parents as well as to people who were employed for draining the pond.

As far as the farmer’s objectives are concerned, fish farming is first of all, an object of prestige and of pleasure; it is more a fish farming of self-consumption; it valorizes the marginal lands since ponds are constructed on non-cultivatable area.

II.3 Conclusion

All these representations of the fish and the fish farming exclude investment in terms of money and labor from the priorities of the farmer. There is no specific production strategy and conducted activities are circumstantial or linked to arising opportunities. It can be observed that practices are linked to these representations. Thus, in order to induce a change in farmers’ representation, more efficient practices ought to be first worked out. This phase is a pre-requisite as it would end in a change in the results and induce a new vision of the activity.

III- PROCESS OF CO-CONSTRUCTING FISH FARMING INNOVATIONS: NEW PRACTICES AND EVALUATION OF THEIR PERFORMANCES

During the restitution of the information gathered during the diagnosis process, collective discussions between researchers and farmers on the current fish farming practices in Fokoué are carried out. From these discussions, new practices are suggested and the two groups agree on testing them. A monitoring and an evaluation protocol is then drawn up and the execution setting is discussed by the two groups: each farmer has to note down in a notebook all the operations achieved in his pond in accordance with a member of the group of scientists. The latter is to stay in the area throughout the production cycle and his role is to facilitate understanding of the new practices by the farmer. The regular restitution of collected information by the researchers to the farmers is regularly done with the aim to update and harmonize the understanding of both groups.

III-1 Structure of ponds

Modifying the shape of a pond is undertaken before its stocking. To this end, close to 50% of fish farmers shall indebt themselves, convinced that it is worth the improvement of their harvests. The construction of bigger ponds (up to 350 m²), compost cribs occupying 10% of the pond surface, deeper ponds (about 1m deep) with a water supply completely under control will therefore be undertaken. Dykes shall also be improved in terms of profile. One of the fish farmers will also construct a piggery of 10 m² over his pond during this phase.

III-2 Acquisition of fingerlings and stocking of the ponds

The stocking of the ponds for testing the new fish farming practices took place between December 2005 and February 2006.

The Nile tilapia fingerlings which were stocked during this production cycle were produced on the farm. Their weights ranged from 5 to 20g. Stocking densities varied from 0.5 to 2 fish/m2. The problem of obtaining Clarias gariepinus fingerlings from hatcheries led researchers and farmers to look for a supply from the wild: the Mbô plain in the Santchou Sub division which is situated at about 30 km from Fokoué. Here, juveniles of this species abound between the months of November and January and are indeed a competitive alternative at a unit cost of 50 FCFA/piece (1 US$ = 500 FCFA) for fingerlings over 20g in weight. Purchases were done on a collective basis. The federation of human and financial possibilities within the group contributed to reducing the cost of the operation. So it was for the 2006 fish farming campaign: close to 2,000 catfish juveniles from Santchou were distributed in Fokoué and pond-stocked were at a rate of 1/m² (Lazard and Oswald 1995). The fingerlings were sorted and calibrated with farmers before their stocking in the ponds.

III- 3 Management of the compost crib in the pond

The manpower related to this task was mainly supplied by family members, regardless of their sex and age. Parents as well as children were called upon to ensure that the crib was always well loaded. However, the task was executed by men in 80% of the cases. The high involvement of men in this activity can be explained by the fact that it requires an important physical efforts and availability. 20% of the fish farmers hired sometimes temporary workers for collecting and/or transporting of some of the inputs (cow dung, pig manure). This recruitment of workers is limited to very beginning of the production cycles during when the initial loading of the compost crib is done since big quantities of input have to be gathered and transported right into the ponds.

The inputs which are used to load the compost crib for the fertilization of ponds and the nutrition of the fish are mainly residues and waste products from other agricultural activities (figure 1).




Figure 1. Type of inputs used and proportion of farmers who use them for compost crib and direct feeding of fish


The important variety of fertilizers and feeds which are used reflects a good level of integration of fish culture with the other activities of the farm. This mobilization of diversified inputs leads to a more regular loading of the compost, four times per week on the average. Loaded quantities varied from 0.75 kg to 6.90 kg/100 m²/d. Farmers who show a better ability to load big quantities of organic matter in their compost generally own a stock of more than five adult pigs and own relatively small ponds (180 m²). The average quantity of materials was 3.7 times higher than what is reported by Brummett (2002) (0.54 kg/100m²/d) for farmers in the peri-urban area of Yaoundé.

The type of integration and its economic success depend largely on the socio-economic characteristics of the exploitation such as the production scale (Milstein 1995). Figure 2 presents the proportions of inputs used as fertilizers and feed for fish depending on their origin.



Figure 2. Proportion of inputs used for fish culture depending on their origin

It is clear from figure 2 that the most used wastes and residues are of animal origin. More than 71% of this animal material is pig dung. This abundant use of pig dung by farmers for pond fertilization could have been inspired by their success in the cultivation of food crops where this input represents one of the most important fertilizers for the other crops on the farm. In addition, the ease and low intensity of required labor can also explain why this input is largely used. According to Milstein (1995), the use of manure in aquaculture could be more profitable than their use as crop farm fertilizer.

III- 4 Fish farming yields

The absence of tilapia fry when draining the ponds means that their populations were relatively well controlled by catfishes. Table 1 presents some characteristics of harvests obtained during the year 2006.

Table 1. Average individual weights and final yields obtained in the year 2006 at Fokoué by 10 farmers

Fish species

Average final

weight in g

Average yields in t/ha/year

Contribution to total yield

Oreochromis niloticus

116±33g

1.8

50.5%

Clarias gariepinus

287±146g

1.2

40,0%

Clarias jaensis

189±44g

0.2

9.5%.


From table 1, we observe that the biomass of tilapia represents more than half of the total yields and that the final average weights of the different species were much higher than those observed at previous harvest in Fokoué. For some of the farmers, obtaining male tilapias of an average individual weight of 300g and catfishes weighing 1000g after only ten months growing cycle was an unavoidable focus of admiration. The possibility to produce these big-size fish became the main topic discussed by the farmers since they had never produced such large fish before. The highest yield obtained by a member farmer was 8.3t/ha/year. It is higher than the production objective which was fixed by farmers and researchers alike at the beginning of the program (5t/ha/year). It is comparable to the potential yields of the semi intensive systems as recommended by Little and Muir (1987).

A principal components analysis of the factors influencing the elaboration of the yields shows that the rate of water renewal in the ponds was the factor which most impacted the yields. It was inversely proportional to yields with a correlation coefficient of -0.6. Water renewal in this production system induces a loss of mineral elements (Boyd 1982). This loss is reflected by a loss in the primary production of the pond, thus reducing the quantity of nutrients available for planktonivorous species. Water should be maintained stagnant and additions should only be made in order to compensate losses due to evaporation (Yong-Sulem et al. 2006).

III-5 Conclusion 

This rearing cycle conducted in partnership between farmers and researchers made us aware of the fact that the Fokoué sub division has an aquaculture potential which can be better exploited if a minimum of technical improvements are implemented, notably with respect to the water management, the supply of fertilizers and the choice of fish species associated in the ponds.

IV. NEW ACHIEVEMENTS AND NEW QUESTIONS: THE STATUS OF FISH CULTURE

The implementation of a set of rearing practices in a participative frame has had the merit of inducing the farmers to question their former practices. This is especially true for the quality of the pond infrastructures, of the management of pond water, of the utility of an in pond compost crib, of the stocking densities and of the role of catfish in the pond to support both the production and the predation on the tilapia fry. As a matter of fact, new achievements induce changes in the farmers’ representation and help enforcing new practices while arising new questions.

At the level of pond structure, prior to the partnership implementation, a pond of 100m2 was considered as a large pond. For the farmers, the link between the surface of a pond, its depth and its production was not clear. Thinking about fish stocking densities in relation with the pond surface will induce farmers to increase surface areas of their ponds. On the contrary to the common believe according to which pond water was to be regularly renewed; the farmers have realized that when the water was not changed over long periods, it became green, and the harvest was better. Hence it became urgent to try to plug up pond bottoms and dykes and agriculture engineering skills will be mobilized in order to develop strategies for reducing water leaking from the fish ponds.

The fish stocking in the ponds is, according to the farmers, their main concern, “tilapia is a fish which does not grow”. Experimentation conducted on mixed-sex tilapia, associated with a police fish (a predator) in the ponds during a production cycle has contributed to transform this belief. The capture of catfish which had fed on tilapia fry enforced the idea according to which the association of the two species was mandatory for controlling the tilapia population which reproduces spontaneously and significantly in the ponds. The farmers therefore realized that the catfish contributes to the production of big sized fish through the control of the tilapia density in an environment where trophic resources are limited.

The strict control of the densities of the different species in the pond was difficult to accept by the farmers. The relation between the number of socked fish, the available trophic resources in the pond and the final average individual weight at harvest is not well appreciated by the farmers. All of them estimated that their ponds were understocked. They are only convinced to farm fish if they can observe the fish moving in their ponds. Besides, this is well illustrated by this sentence of a farmer say: ”Empty ponds will not be fed, there is room for more fish”. Curiosity associated with the belief that the researchers won’t mislead them contributed to induce the fish farmers to adopt the recommended lower densities. However, some distrust persisted in the mind of a few farmers. Without informing, the researchers, one of them increased the number of tilapias in his pond. It is the fish weights at the end of this cycle which will finally convince the farmers to stock a quantity of juveniles which matches the trophic capacity of the ponds. Beside the advantage of using a predator, the supply of Nile tilapia fingerlings is becoming a problem, the catfish having eaten all of them. It becomes urgent for researchers and farmers to develop strategies to produce tilapia fingerlings separately. This new worry shall be the object of a research protocol during the next rearing cycle. This new management falls in line with the observations of Osure et al., (2005) who questioned whether low Nile tilapia yields were due to genetic depression through inbreeding or to the rearing practices of the farmer.

The great variety of inputs used by farmers emphasized the possibility of integrating the production of fish with the other farming activities. The farmers also noticed that, to maintain the green color of the ponds (a good indicator of their productivity), regular supplies of animal manure were mandatory. The predominant use of by-products and other waste at Fokoué are more closely linked to uncertainty about the yield that can be obtained than to lack of financial means and availability of well elaborated feeds. Henceforth, inputs like pig manure shall be directly poured into the ponds instead of into the compost crypt. The use of in pond composts has been criticized by farmers since their management is very laborious. The lack of tools which are adapted for turning them as recommended makes them become compact blocks where the organic matter decays anaerobically. The production of methane has even been observed by Efolé (2008).

The appreciation of the predation impact was no more the same after this cycle. After the draining of the ponds, almost 70% of the stocked catfishes were harvested. Sibling cannibalism between catfish was the main cause of their disappearance from ponds. The stocking of small and not homogeneous fingerling sized catfish exacerbates this cannibalistic behavior (Sulem et al., 2006).

The harvests at the end of this rearing cycle were largely above the hope of the farmers, as well with respect to individual average weights as to the total biomass. The pond draining attracted crowds which were curious to “see and know about the practices which led to yielding of such big fish”. The positive impression of farmers about the fish harvests is such that they all yearn to make the set-ups which are necessary for increasing their production in order to be able to sell more fish.

The new achievements do not only benefit the farmers but also the researchers. In terms of production, obtaining yields of close to 8t/ha/yr, male tilapias of 300g and catfish of close to 1000g in 10 months show that in the Western province where temperatures are far from the optima for these species, it is possible to set up a significant fish production through using local resources.

These satisfying fish yields are also a guarantee of the continuation of the working partnership. If the production problems are being partly solved, those related to the organization of the farmers and to the commercialization of their products are still being studied.

V-CONCLUSION 

After this first production cycle during which the focus has been put on socio-technical aspects of fish culture, it can be assessed that fish farming practices anterior to the research in partnership were reflecting a poor knowledge of the basic farming principles. A better follow-up of these last on-farm experiments has contributed to the evolution of farmer practices. Fish farming is no more only an activity of prestige or pleasure; it is more and more perceived as a source of income. The yields obtained at the end of the rearing cycles are responsible for the changes in the farmers’ representation. The results presented here are in favor of working on the evolution of practices in order to induce a change of the farmer’s representations. Indeed, reducing the fish stocking densities in the ponds implies that their representation of the fish (as an object of pleasure and leisure) is being swapped for the representation of the fish as an animal which should find enough to eat in order to grow. The farmer’s objective is no more just to have a lot of fish in the ponds but to have fish of individual weights matching the expectations of the consumers (> 200g and 600g for tilapia and catfish respectively).

The implemented « Research Action partnership » approach has permitted the creation of a new link between the farmer and the scientist. The position occupied by the latter gives him the possibility of having a real vision of farmer’s assets and constraints. This position leads to the possibility to conceive, in interaction with the farmers, modes of action aiming at an optimal exploitation of the resources available for the fish production. The scientist finds himself playing the role of an adviser to the farmer, as, beyond the fish culture activities which are his entry gate into the family farm. His opinion is more and more requested on other activities of the farm.

This approach leaded to the identification of some strong constraints which had been hindering the fish culture development in the area:

  • the too important renewal of the pond water,

  • the lack of a common production model of which the technical itineraries and different alternatives are mastered, the insufficient assistance to farmers.

A weakness which could affect the efficiency of this approach is the difficulty of taking into account technical, the economic and organizational problems at the same time. This highlights need for a multi-disciplinary team. Moreover, the proximity which should exist between the farmer and the researcher requires an important investment in time and in labor. The evolution of the practices and of the farmer’s representations through the collaborative research process have been very significant indeed BUT what has been acquired is still fragile and should be re questionned in the course of the next production cycles.

The aim of this work was to initiate thoughts related to the representations that farmers have of their own activities. The evolution of these representations could lead toward a commercial and profitable fish-farming.

ACKNOWLEDGEMENT

We thank the REPARAC project for having financed this study, as well as farmers of the COPIFOPEM CIG and the PEPISA CIG for their frank collaboration.

REFERENCES

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